The present invention relates generally to gas turbine engines and, more particularly, to a detachable burner tube for use with a gas turbine engine.
Known fuel nozzle assemblies mix air and fuel for combustion. A burner tube assembly is the outermost component of at least some known fuel nozzle assemblies and is designed to protect a plurality of internal components within the fuel nozzle assembly while channeling the air/fuel mixture through the fuel nozzle assembly. Within at least some known burner tube assemblies, a plurality of components are welded together along a plurality of seams.
Assembling known burner tube assemblies, specifically the welding process, may be a difficult task. For example, inlet air flow is determined by the burner tube assembly at the time of assembly and is generally inflexible to any subsequent changes. More specifically, to implement a design change to the air flow generally requires replacement of the entire fuel nozzle assembly. In addition, during assembly, any damage to the burner tube assembly itself may require a repair of the entire fuel nozzle assembly. The assembly process is further complicated by the burner tube assembly, which limits access to the internal components of the fuel nozzle assembly, thus making such components difficult to inspect and service.
Within known fuel nozzle assemblies, the burner tube assembly is designed such that the air flow becomes substantially uniform as it flows downstream. During operation, however, the seams created between the components coupled together may create flow anomalies, such as recirculation zones, that may adversely affect the operation of the fuel nozzle assembly. As such, during assembly, each joint requires special attention to prevent flame holding issues wherein trapped fuel and air may automatically ignite. Moreover, some known burner tube assemblies are not coupled to a support flange, and, in such tubes, a first natural bending frequency of the fuel nozzle assembly may be low enough to be excited by rotor speed multiples, thus increasing a risk of part failure due to vibration.